This invention relates generally to microwave devices, and more particularly, to a ferrite circulator having integrated alignment members.
Ferrite circulators are typically configured as multi-port (e.g., three-port) passive RF or microwave devices having magnets and ferrite material that may be used to control the direction of signal flow in, for example, an RF circuit or a microwave circuit. For example, ferrite circulators may be used to control signal flow in wireless base station or power amplifier applications.
In general, a ferrite circulator or junction ferrite circulator is a multi-port device, such as a three-port device, having a symmetrical Y-junction formed by a magnetically biased ferrite disk or slab that is often used as a diplexer. The circulator allows flow of, for example, microwave energy in one direction (e.g., from one of three ports to another one of the three ports). In operation, a microwave signal entering one of the ports of the ferrite circulator follows a rotating sense based on the interaction of the electromagnetic wave with the magnetized ferrite. Thus, by symmetrically constructing the ferrite circulator, a defined signal path or direction through the ferrite circulator may be provided. Ferrite circulators also may be used to protect against reflections by terminating one of the ports of the ferrite circulator to thereby provide isolation.
In order for the ferrite circulator to properly operate (e.g., properly control signal flow therethrough), proper alignment of ferrite within the ferrite circulator must be provided. Specifically, the ferrite and center conductor must be precisely positioned and maintained relative to the housing in order to provide proper operation. It is known to provide alignment devices in connection with the ferrite circulator and/or to use epoxy to ensure proper alignment of the ferrite within the housing of the ferrite circulator. For example, it is known to use a plastic aligning frame or aligning disc member in connection with the ferrite circulator to ensure proper alignment of the ferrite within the housing of the ferrite circulator.
These known alignment devices add complexity and cost to the ferrite circulators. Further, the likelihood of misalignment of ferrite within the housing of the ferrite circulator increases due to improper positioning or affixing of the alignment device within the housing.